You can find various versions of the documentation through official and community sources: SIPROTEC 5 7UT82/85/86/87 Trans... - Support - Siemens

serves as the base entry in the 7UT8x series, providing a cost-effective, compact solution for standard transformer protection . While its siblings (7UT85/86/87) handle more complex three-to-five winding configurations, the is optimized for efficiency in two-winding applications . Reliable Protection Core : At its heart, the

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The manual has a table of LED states. A flashing "ERROR" does not always mean relay failure—it may indicate a CT supervision alarm. Refer to Chapter 5.4 "LED Indications."